/**
* @author AlbertDarren
* @contact 2563491540@qq.com
*/
#include <iostream>
#include <string>
using namespace std;

int main_22()
{
    string email="2563491540@qq.com";
    int sep=email.find('@');
    string username=email.substr(0,sep);
    cout << username << endl;
    string domainName=email.substr(sep+1);
    cout << domainName << endl;
    string maxSubStr=email.substr();
    cout << maxSubStr << endl;
    email=username.append("@163.com");
    cout << email << endl;
    email.replace(0,email.find('@'),"albertdarren");
    cout << email << endl;
	return 0;
}
